If you're looking for something to do outdoors on Amelia Island, Amelia Island State Park sits high on the list for anyone who's spent real time here.
A natural area at the southern tip of the island at Nassau Sound, where the main draws are guided horseback rides on the beach through Kelly Seahorse Ranch, surf and pier fishing, and birding across salt marsh and maritime forest. It's one of the few beaches in Florida where horseback riding is permitted. Admission is $2 per person via honor box.
Located in Fernandina Beach, it's within a short drive of most parts of Amelia Island.
The venue reads as State Park, Horseback Riding, Fishing, Birding based on its own positioning, which is a useful signal if you're trying to match it against what you're actually in the mood for.
For current hours, rates, and anything else that changes season to season, the park's own site at https://www.floridastateparks.org/amelia-island is the source to check; nothing on this page invents a detail that isn't on theirs.
For visitors planning a fuller day on the island, concierge service can line up reservations, transportation, and the surrounding logistics so the day itself is the only thing to focus on.